The present disclosure relates to reducing the formation of paper edge ghost in image forming apparatus that include photoreceptors.
A common issue with image forming apparatus using photoreceptors to produce images is the phenomenon called paper edge ghost. When an image forming apparatus, such as a photocopier, is used to produce a large number of images on one size paper over an extended period of time, and then, the same photocopier is used to produce images on a larger sized paper, a latent image can be seen in the image formed on larger sized paper. This artifact represents the edge of the previously-formed smaller sized paper. The paper edge ghost is visible in an image printed on the photoreceptor that traverses the areas previously covered by the smaller paper and the bare photoreceptor.
The effect of the paper edge ghost can be reduced by shifting the location of each image formed on the photoreceptor during the image forming process. However, when the image location is shifted, the position of the recording medium (for example, paper sheet) that receives the image from the photoreceptor also must be shifted so as to properly receive the image from the photoreceptor. Although it is possible to shift the image and the recording medium in the process direction (the direction in which the photoreceptor moves during image formation) relatively easily by controlling the timing of image formation and sheet feeding, it is more difficult to shift the image and recording medium in the cross-process direction (the direction crossing the process direction).